For the purpose of extracting material along a longwall face in an underground mine, a shearer with two cutting drums may be provided. As is known per se, the shearer reciprocates along the longwall face to extract material with the two rotating cutting drums. Extracted material is dropped onto a face conveyor extending along the longwall face to transport the extracted material to a roadway for further processing.
Control of the shearer typically requires operator assistance, for example, to guide the cutting drums in accordance with the material seam to be extracted. As an underground mine is a tough and hazardous environment not only for the mining equipment, but also for the mining equipment operators, providing methods for controlling the shearer along the longwall face, which require reduced operator assistances, are subject of ongoing interest of mining equipment manufacturers.
For example, EP 1 276 969 B1 discloses a mining machine which moves from side-to-side in sequential passes across a seam of material to be mined. The machine is carried on rail means and coordinate positions of the rail means are measured at locations along the length of the rail means. A trailing part of the rail means is then moved by rail moving means to a new position for a next pass, and the distance of moving is determined from the co-ordinates of the positions previously measured. Coordinates of the up and down movement of a shearing head can also be measured and stored to provide a profile of the seam being cut, and so that on a next pass the intended position of the shearing head can be predicted and moved accordingly.
As a further example, U.S. Pat. No. 4,822,105 A discloses mining methods for a shearer. An operator manually manages or handles the drums during half of an operation cycle, and heights of respective right and left drums at respective travelling positions and inclined angles of a shearer body are stored in a teaching mode. The next half-cycle operation can be achieved by a playback operation mode. Thereby, a constant working height of a mining face under controlled condition is maintained.
As yet another example, US 2003/0075970 A1 discloses a mining machine that moves from side-to-side in sequential passes across a material seam to be mined. The machine is carried on rail means, and co-ordinate positions of the rail means are measured at locations along the length of the rail means. A trailing part of the rail means is moved to a new position for a next pass. The distance of moving is determined from previously measured positions to assume a desired profile, preferably a straight line.
The present disclosure is directed, at least in part, to improving or overcoming one or more aspects of prior systems.